Brake-shoe adjuster.



0. S. MGCURDY.

BRAKE SHOE ADJUSTER.

APPLICATION FILED JAN 1?, 190a,

Patented Oct. 5, 1909.

STATES PATENT OFFICE.

' ocean s was, or wmxmsnunc, nimvazpvnnm, ASSIGNOD To run wns'rmanousnAIR BRAKE COMPANY, or rrr'rsnum, PENNSYLVANIA, a conrom'rzon orPENNSYLVANIA.

Specification of Letters .Patent.

, BRAKE-slice ADJUSTER.

Patent-ed Oct. 5, 1909.

Application filed January 17, 1908. Serial No. 411,225.

Adjusters, of which the following is a. specification.

My invention relates to devices adapted to automatically compensate forthe wear of the brake shoe and maintain the normal release distancebetween shoe and wheel or other engaging surface substantially constant.

.My invention has special reference to a brake of thattype wherein thedragging action ofa brake shoe on the rail is emplo to apply brake shoesto the wheels, an the rincipal object of my invention is to providb abrake shoe adjustin device in a brake of the above character w ich isoperated by the dragging action of the rail brake shoe for maintainingthe distance be- 'tween the wheel brake shoes and the wheelssubstantially constant in normal release position.

,to the car truck frame.

In' the accom anying drawing; Figure 1 is an elevational view of a carbrake of the above character, with a preferred construction of myinvention applied thereto; and

Fi 2 a sectional view of a portion of the "adjusting mechanism taken onthe line a-a of Fig. 1.

Accordin to the construction illustrated in Figf'l 0 the drawing, thecar brake may com rise a. rail brake shoe 1, which is suspen ed abovethe rail on springs 2, supported in position by adjustable bolts 3,which'are mounted in a bracket-4 secured K Wheel brake shoes 5 are susended in position adjacent the wheels 6, 1 1 pivotally mounted angers";i

wit

one end to ush bars 9, which are connected to the rail rake 1, and theopposite ends of the levers 8 are connectedv together by a rod 10. V

' As thus far described, the construction 1s substantially the same asthat covered in Reissue Patent No. 11,786, dated November 7, 1899.Therail brake in this patent being provided with an electrical coll wmdmso that upgn sending a current of electricity therethrougli, the railshoe acts as a magnet and is attracted to the rail, causing the draggingmovement thereof, which acts through they push rods and levers to applythe wheel brakes.

For adjusting the clearance between brake shoe and wheel I preferablyprovide a downwardly projecting rocker arm 11, which maybepivotally-mounted on a bolt 12, secured to the car frame, and anadjusting bar 13, havmg a yoke 11 on one end fitting over the rocker arm11 and slotted for the bolt 12 to is slotted to contain a spring pressedpawl 16. The casing 15 contains a ratchet wheel 17, which is mounted onthe rod 10, said casing being rovided with apertures on opposite sidesor the rod 10. The pawl 15 is adapted to engage lhe'teeth of the ratchetwheel 17, so that the downward movement of the adjusting bar 13 tends toturn the ratchet wheel 17, and the upward movement of the bar to causethe pawl to ride over the ratchet teeth.

On the top of the rail brake shoe 1, and in line with the rocker arm 11,are secured lugs 18, which are so positioned that when the draggingmovement of the brake shoe 1, necessary to bring the wheel shoe 5 to thewheel, has increased a certain predetermined amount, by reason of thewear of the wheel shoe,'one of the lugs 18 will strike the de-' pendingend of the rocker arm 11 and cause one of the fingers 19 thereon toelevate the adjusting rod 13, so that the pawl 16 is lifted into ahigher tooth on the ratchet wheel 17, and then upon the usual release ofthe brakes; the rocker arm 11 assumes its normal vertical position, andthe adjusting bar with the pawl moves downwardly, turning the ratchetwheel the amount of onetooth. If desired, a spring 20 may be interposedbetween the casing 15 and the yoke 14 to facilitate the downwardmovement of the adjusting rod 13. The turnin of ratchet wheel 17 may beutilized in di erent ways for adjusting the brake shoes toward thewheels, but preferably I provide right and left hand threads on theopposite ends of the e ualizing bar 10 respectively, for screw threa edengagement with nut members 21, pivotally secured to the levers 8. Itwill now be apparent that by turning the ratchet wheel 17 and bar 10 thenut portions 21 may be shifted outwardly, thereby settin the brake shoesrelatively nearer to the w eels. Thus I have constructed a simple devicewhereby the wheel shoes may be maintained at a substantially constantdistance from the wheels in normal release position.

In order to hold the pawl 16 away from the ratchet wheel 17, in case theadjusting rod 13 is moved up for the purpose of adjusting the rod 10 byhand, I may provide a pin 22, secured to the rod 13 and adapted toengage in a slot in the pawl 16, so that the outward movement of thepawl 16 will be limited.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is 1. The combination with a plurality of brakeshoes, of means 0 rated by one brake shoe for ad usting anot er one ofsaid brake shoes.

2. The combination with a plurality of brake shoes, of means operated byone brake shoe for adjusting the other brake shoes.

3. The combination with a lurality of brake shoes, of means operated ythe draging movement of one brake shoe, for adustmg the other brakeshoes.

4. In a car brake, the combination with a rail brake shoe and wheelbrake shoes applied by the dragging movement of the rail brake shoe, andmeans 0 erated by said dragging movement for ad usting the wheel brakeshoes.

3:. In a car brake, the combination with a rail brake shoe and wheelbrake shoes applied by the dra ging movement of the rail rake shoe, anmeans 0 erated by said dragging movement for ad usting the wheel brakeshoes to compensate for wear.

6. The combination with a luralit of brake shoes, of means operatedy-the d gin movement of one brake shoe for a ustmg the other brake shoesto compensate for their Wear.

7. In a car brake, the combination with a brake shoe and wheel brakeshoes applied by the dragging movement of said brake shoe, of an adustable screw operated by said dragging movement to compensate for theWear of said wheel brake shoes.

8. In a car brake, the combination with a brake shoe and wheel brakeshoes applied by the dragging movement of said brake shoe, of anadjusting device adapted to com ensate for the wear of the Wheel brakesioes and a rocker arm operated by the dragging movement of said brakeshoe, for actuating said adjusting device.

9. The combination with a brake shoe, of a brake shoe adjustingmechanism operated by the dragging action of said shoe.

10. The combination with a brake shoe, of a brake shoe adjustingmechanism adapted to compensate for the wear of a brake shoe andoperated by the dragging action of said brake shoe.

In testimony whereof I have hereunto set my hand.

R. F. Emmy, WM. M- Qatar.

